Patent classifications
G01V2210/6224
SETTING A WELLBORE CASING IN A SALT FORMATION
A method for setting a wellbore casing in a subterranean formation is described. The method includes: drilling a test wellbore in the subterranean formation; generating a density profile of a plurality of geological layers above a salt formation in the subterranean formation based on observations from the test wellbore; calculating an overburden stress imposed on the salt formation by weight of overlying formation based on the density profile of the plurality of geological layers; performing creep mechanical behavior tests on core samples from the salt formation to generate a strain-time curve for the salt formation; calibrating multiple analytical creep models with mechanical properties of the salt data generated by the creep mechanical behavior tests; implementing a wellbore closure model based on a best-fit analytical model and mechanical properties of the multiple analytical creep models; drilling a well; and setting a casing through the salt formation.
System and method for application of elastic property constraints to petro-elastic subsurface reservoir modeling
An information processing system having a processor and a memory device coupled to the processor, wherein the memory device includes a set of instruction that, when executed by the processor, cause the processor to receive a multi-dimensional grid of acoustic or elastic impedances determined from seismic survey data associated with a subterranean formation, receive elastic property data that describes elastic property characteristics used to sort pseudo-components, and wherein the respective pseudo-components are formed of a combination of two or more lithologies. The instructions, when executed by the processor, further cause the processor to define select design variables using the impedance arrays, perform optimization operations for optimizing select design variables by applying the elastic property data as a part of a constitutive relation, and output a distribution of the pseudo-components to characterize volumetric concentrations of spatially grouped lithologies in a control volume of the subterranean formation.
Elastic full wavefield inversion with refined anisotropy and V.SUB.P./V.SUB.S .models
Methods for inversion of seismic data to infer subsurface physical property parameters, comprising constructing an inhomogeneous anisotropy model and/or inhomogeneous V.sub.S/V.sub.P or V.sub.P/V.sub.S model; and inverting the seismic data in a sequential or simultaneous approach to obtain at least one subsurface physical property parameter using an elastic inversion algorithm and the inhomogeneous anisotropy model and/or inhomogeneous V.sub.S/V.sub.P or V.sub.P/V.sub.S model. Constructing an inhomogeneous anisotropy model may comprise deriving geobodies from at least one of seismic facies analysis, regional geologic information, or seismically derived earth models; and adjusting at least one of ε, δ, γ, or parameters of the elastic stiffness tensor matrix in a homogeneous anisotropy model in areas corresponding to the geobodies. Constructing an inhomogeneous V.sub.S/V.sub.P or V.sub.P/V.sub.S model may comprise deriving geobodies and adjusting values in a homogeneous V.sub.S/V.sub.P or V.sub.P/V.sub.S model in areas corresponding to the geobodies.
System and method for predicting fluid type and thermal maturity
A method for determining a thermal maturity image of a subterranean region and a non-transitory computer readable medium, storing instructions for executing the method, are disclosed. The method includes, obtaining a seismic dataset for the subterranean region of interest, obtaining a thermal maturity value for a plurality of core samples taken from different positions within the subterranean region, and obtaining a plurality of well log types from the core sampling location. The method further includes determining a calibrated rock physics model based on the plurality of well log types, determining a pore fluid type based on the calibrated rock physics model, and determining a thermal maturity model based on the plurality of core samples, on the pore fluid type, and on the plurality of well logs. The method still further includes determining the thermal maturity image of the subterranean region based on the seismic dataset and thermal maturity model.
Setting a wellbore casing in a salt formation
A method for setting a wellbore casing in a subterranean formation is described. The method includes: drilling a test wellbore in the subterranean formation; generating a density profile of a plurality of geological layers above a salt formation in the subterranean formation based on observations from the test wellbore; calculating an overburden stress imposed on the salt formation by weight of overlying formation based on the density profile of the plurality of geological layers; performing creep mechanical behavior tests on core samples from the salt formation to generate a strain-time curve for the salt formation; calibrating multiple analytical creep models with mechanical properties of the salt data generated by the creep mechanical behavior tests; implementing a wellbore closure model based on a best-fit analytical model and mechanical properties of the multiple analytical creep models; drilling a well; and setting a casing through the salt formation.
AN INTEGRATED GEOMECHANICS MODEL FOR PREDICTING HYDROCARBON AND MIGRATION PATHWAYS
The present invention relates to a method of prediction of hydrocarbon accumulation in a geological region comprising the following steps of: a. Generation of a geological basin model; b. Generation of a geomechanical model; c. Generation of an integrated model; d. Generation of a strain map based on the information obtained in steps a to c; e. Prediction of hydrocarbon accumulation from the strain maps.
Methods and devices correlating well-logs to cuttings lithologies for synthetic core generation
An exploration method starts from cuttings associated with sampling intervals and well data for a well in a subsurface formation. The cuttings are prepared and analyzed to extract textural and chemical/mineralogical data for plural fragments in each sample that is made of the cuttings in one sampling interval. The method then includes matching lithotypes of rock defined according to the textural and chemical/mineralogical data for each fragment with segments of the well data in the corresponding sampling interval to obtain correspondences between the lithotypes and depth ranges. The correspondences between the lithotypes and the depth ranges may be used as constraints for seismic data inversion.
Borehole dispersive wave processing with automatic dispersion matching for compressional and shear slowness
Disclosed are systems and methods for processing acoustic logging information with automatic dispersion matching. The method comprises obtaining, from an acoustic logging tool, acoustic waveforms from within a borehole, applying dispersion analysis to the acoustic data to extract a slowness-frequency response, calculating a slowness density log of the slowness-frequency response, obtaining an initial shear slowness estimate based on the slowness density, generating a dispersion model comprising model parameters, and performing a dispersion response auto match inversion to minimize the difference between the slowness-frequency response and the dispersion model in order to obtain a final shear slowness estimate.
Downhole fluid density and viscosity sensor based on ultrasonic plate waves
Methods, systems, and devices for downhole evaluation using a sensor assembly that includes a sensor plate, wherein a surface of the sensor plate forms a portion of a surface of a downhole tool. Methods include bringing the surface of the sensor plate into contact with downhole fluid; generating a guided wave that propagates in the sensor plate by activating the sensor assembly at at least one frequency configured to excite both a symmetric mode and an anti-symmetric mode; making at least one first attenuation measurement of the symmetric mode of the guided wave; making at least one second attenuation measurement of the anti-symmetric mode of the guided wave; and using the at least one first attenuation measurement and the at least one second attenuation measurement to estimate at least one parameter of interest of the fluid. Methods may include submerging the surface of the sensor plate in a downhole fluid.
LINEAR CALIBRATION METHOD FOR LITHOSTATIC STRESS RESULTS FROM BASIN MODELING
A method, a system, and a non-transitory computer readable medium to calibrate a lithostatic stress map of a particular geological layer in a basin model are described. The lithostatic stress map is generated by simulating the basin model and calibrated based on available well data without re-simulating the basin model. In particular, the calibration is based on the mean lithostatic density, which is a constant value of density that yields a value of lithostatic stress equivalent to the lithostatic stress at the same depth produced by the existing column of rocks in the basin.